A Saturday night fire at a Mankato apartment building is being called a case of arson. The fire at the Homestead Drive apartments was contained to an entryway. A fire alarm system automatically closed a fire door and notified authorities, preventing the fire from spreading and allowing firefighters to quickly extinguish it. Damages to the building were minor, and are being estimated at $1,500. No injuries were reported. Anyone with information on this fire is asked to contact their local authorities.